Traditional drum distribution techniques in nursing homes and hospitals suffer from a number of significant problems which may result in poor patient care and an increase in cost to the patient or the hospital. In the filling of a typical prescription, the pills are packaged in a container with a label giving, among other things, the name of the patient and the number of times a day the pill is to be taken. The number of pills in the container is generally sufficient to meet the patient's needs for several days. In nursing homes and hospitals, it is not uncommon for a particular patient to be prescribed several different types of pills with different combinations of those pills to be dispensed at different times of the day. It is up to the nurse to be sure that the correct pills are dispensed at the correct time and that the nurse chart for each patient what pills were dispensed when. Often, even though it is poor practise, the person dispensing pills in a ward will dispense pills to all of the patients in that ward after which he or she will chart from memory what pills were dispensed to what patient.
Such traditional dispensing methods suffer from a number of disadvantages. It has been estimated that as much as 18% medication errors occur in such methods. Further, especially when dangerous drugs, pilferage remains a major problem. Also, if the patient is taken off a particular drug, he must bear the cost of all of the pills which were packaged in the container for him, since they cannot be returned to the pharmacy. This results in a large amount of waste, greatly increasing the cost of both the hospital and the patient.
In order to overcome the problems associated with traditional medication dispensing methods, a unit-dose procedure has been initiated in many hospitals and nursing homes. In unit-dose, the particular dose of a particular pill to be taken by the patient at a given time is packaged individually in dispenser packs or trays which are labeled for each patient. The key advantages of the unit-dose method over traditional drug distribution systems include minimizing the medication handling from the time it is packaged by the pharmacy until it is taken by the patient, as well as eliminating the time required at the nursing home or hospital for counting and pouring the prescribed dosage of a particular medication. Also, by packaging each dose in a clean container all doses not used may be returned to the pharmacy and reused. Such packaging, because it does minimize handling, also minimizes the chance of contamination of the medication. Such unit-dose procedure has been favorably received by hospitals and nursing homes since it minimizes the nursing time spent in preparing medication. Also, it cuts down the drug cost to the patient, since he is only charged for what the receives, and it increases the degree of accounting and reliability, which in turn decreases pilferage and mistakes.
However, unit-dose procedures as they are now carried out suffer from a number of disadvantages which for many hospitals and nursing homes make the procedures economically prohibitory. Unit-dose packaging equipment is expensive, and much more time is required on the part of the pharmacist to repack the prescribed pills into unit-dose containers. Many dose systems now require delivery of medication to the nursing home or hospital wards at least once a day, and as many as four times daily to cover emergency situations. Major drug companies are now making available their high volume pills in unit-dose packages, but it is impossible from a manufacturer's viewpoint to have all variations of doses premade that a physician may desire. Also, the pharmacist must still prepare the doses required for the patients at a particular time. Thus, the increased efficiency and reliability obtained from unit-dose procedures must be paid for in increased pharmacy costs.
Automatic dispensing apparatuses have of course been used for dispensing a wide range of materials. Pill dispensers which in one way or another dispense a single dose of a particular pill are also known. For example, Gayle U.S. Pat. No. 3,227,127 discloses a pocket size pill dispenser which dispenses a pre-determined number of pills at a particular time. The dispenser contains a time indicating means to insure that the patient does not miss a dose or take a double dose of the prescribed pills.
For narcotic pills, locking dispensers have been devised in which a dose can be dispensed only by authorized personnel. For example, Cantu et al U.S. Pat. No. 3,206,064 discloses a narcotic dispenser into which is inserted a tablet magazine containing a number of pills, and which are dispensed one at a time by pressing a plunger after the magazine has been unlocked. Such devices are a step in the right direction for minimizing mistakes and preventing pilferage, but they do not lend themselves to the servicing of a nursing home or a hospital ward, where generally several pills must be dispensed to each patient, and there are a large number of patients which must be serviced at each nursing station.
It is thus apparent that there is a need for an apparatus and method of filling a patient's prescription in unit-dose quantities which minimizes time and cost for both the pharmacy and the hospital. Also, the apparatus and method at the time of dispensing should lend itself to accounting for all of the pills dispensed, so as to minimize mistakes and pilferage. Since many patients are prescribed more than one pill at a given time, it is also required that the method and apparatus have the capability to dispense a number of different type pills.
Utilizing the dispensers of Gayle or Cantu et al., it is apparent that a large amount of both pharmacy and nursing time would be required to individually fill and individually dispense a separate dose from individual dispensers for every different type pill required by each patient.
Good hospital and nursing care practise also contemplates discretion on the part of the nurse with regard to whether or not all of the pills prescribed at a particular time should actually be dispensed to the patient. For example, if the patient were prescribed a heart medication such as lanoxin, it is good and accepted practise that such a pill should not be dispensed if a patient's pulse is below 60. Thus, it is essential that any unit-dose method have build into it the ability to select which of the pills prescribed should actually be dispensed.
The electronic system of the present invention includes a keyboard and circuits for entering dispensing time, such as 9:00 a.m., 1:00 p.m. and 9:00 p.m., and for entering the number of the cassette or cassettes of the dispensing apparatus which are to dispense pills at the programmed time. The electronic system further includes interlock means to prevent the entry of a different time once a time has been entered, and includes sequencing means for interrogating a logic system for each of the cassettes so as to provide a sampling sequence for the cassettes and to activate the approximate cassettes for dispensing pills. The logic system operates control solenoids for indexing each selected cassette during the dispensing cycle, and the logic system further provides clocking signals to initiate the sequencing operation of the next cassette in order after a preceding cassette has completed its indexing cycle.
Accordingly, it is an object of this invention to provide an improved electronic system for use with apparatus for dispensing articles, such as pills, and in which a prescribed unit-dose or more than one type of pill may be quickly dispensed.
It is a further object of this invention to provide an electronic system for dispensing apparatus which will allow the person dispensing pills to readily and simply select the time and programming of the dispensing cycle.